EXTRAS = {
	// Event listener by Scott Andrew (www.scottandrew.com):
	insertarEvento : function(obj, evType, fn, useCapture){
		if (obj.addEventListener){
			try {
				obj.addEventListener(evType, fn, useCapture);
			} catch (e) {}
			return true;
		} 
		else if (obj.attachEvent){
			var r = obj.attachEvent("on"+evType, fn);
			return r;
		} 
		else {
			return false;
		}
	}
}